1. Field of the Invention
The present invention relates to a resource allocation and power control method. More particularly, the present invention relates to a resource allocation and power control method for an uplink frame in a mobile communication system.
2. Description of the Related Art
A conventional mobile communication system has a problem in that performance of a terminal located in a boundary region of a service coverage area of a serving base station is reduced because of interference caused by uplink data transmitted by a terminal located in a service coverage area of a neighboring base station. More particularly, when the serving base station broadcasts values of noise and interference measured from the service coverage area of the neighboring base station, the terminal of the serving base station increases the strength of its transmission signal in order to compensate for the interference from the terminal of the neighboring cell, and hence, compensate for performance of the terminal located in the boundary region of the service coverage area of the serving base station.
To address this problem, the serving base station classifies its service coverage area into frequency bandwidths for a central region and a boundary region according to the Fractional Frequency Reuse (FFR) method. The serving base station reuses the frequency bandwidth used for the boundary region of the neighboring base station in the central region of the serving base station and controls the transmission power to further avoid interference. Here, the serving base station and the neighboring base station exchange needed information through communication between the base stations so as to efficiently control interference. Also, the serving base station and the neighboring base station transmit control information for use by the terminal of the neighboring cell to reduce power of the uplink data which influences the terminal located in the service coverage area of the serving base station.
However, if the serving base station cannot establish a communication channel with the neighboring base station, the serving base station cannot exchange information with the neighboring base station, and hence, the serving base station must estimate interference from the service coverage area of the neighboring base station by measuring the signal received from the neighboring base station. The serving base station must also minimize interference applied to the service coverage area of the neighboring base station by the corresponding terminal by controlling uplink power for the terminal located in the central region of the corresponding base station. However, if a communication channel is not established between the serving base station and a neighbor base station, the interference estimation and control of transmission power by the serving base station becomes difficult.
Accordingly, there is a need for an improved method for providing a communication service when communication between base stations is unavailable.